The present invention concerns a surgical instrument, specifically a pivoting laryngoscope having a power-driven, curved spatula, used for performing intubation of patients under anesthesia or in resuscitation.
As it is known, before performing surgery, it is necessary to anesthesize the patient. Anesthesia is obtained through drugs which work to completely suspend pain sensitivity in a temporary and reversible way. The anesthetic effect, generally obtained by using alcaloid drugs and muscle relaxants, affects the brain, the cerebellum, the spinal cord and the peripheral nervous system in general, and is furthermore accompanied by a paralysis of the respiratory centers, variable only in intensity and duration exclusively through the use of different drugs.
It is well known that prolonged paralysis of respiratory centers, causes brain damage and, in cases where the duration of the drugs' effect has extended itself beyond a given amount of time, death from asphyxia.
In surgical practice, when the patient undergoes anesthesia, artificial respiration is given by means of external machinery specifically designed for this purpose, after having connected the patient to the same through cannulae and tubes. Connecting the patient to the machine requires a significant amount of manual maneuvers, generally executed by the anesthesiologist, which in medical practice are known as "intubation", consisting of the introduction of a tube or cannula through the mouth, the larynx and trachea to the lungs, the tube being then connected to tee respiratory machinery.
In order to understand the problem, it must be taken into account that the above-described maneuver must be executed with means and within a time frame defined by the progressive paralyzing effect upon the respiratory centers generally brought about through alcaloid anesthetics and muscle relaxants or other similar drugs. Therefore, the duration of the intubation process cannot extend itself beyond a generally brief and definite time frame, also because of the mechanical difficulties inherent to the introduction of the cannula of tube.
Usually, in order to execute the intubation maneuver, the anesthesiologist uses a mechanical instrument, typically a spatula-tube mounted at a right angle on a handle, of the same type as that which is used to execute laryngoscopies, bronchioscopies or esophagoscopies. The instrument having been introduced in the patient's mouth, the anesthesiologist reaches, by means of the spatula, the base of the toungue and the laryngeal wall of the epiglottis and with a quick pivoting movement straightens the spatula-tube into an almost vertical position, and then, with small, slow motions, introduces the cannula along the laryngeal cavity.
The manner of execution of this maneuver, as traditionally executed and with the known instruments, presents some inconveniences.
First of all, it must be noted that the maneuver needs to be executed by pivotally moving the cannula-guiding instrument, in order that the lowering of the toungue and the dental arch allows the cannula to travel along the medial line of the trachea in an axis as direct as possible to the point of introduction, that is, the mouth.
Such a pivoting movement, is obviously not obtainable by using an instrument having the cannula-guiding spatula placed at a right angle to the handle. Similarly a curved spatula does not resolve the problem since such a curve, being permanently set, could not be adapted to the multiple positions which are produced by the rotation of the head and the neck in various situations.
The intubation maneuver operator frequently operates on patients having acquired pathologies, such as cervical arthrosis or mandibular anchylosis, or having congenital deformities such as macroglossis (overdevelopment of the toungue) or "bull neck", which make it extremely difficult, if not impossible, to introduce an intubation cannula guided by an instrument which depends on its being pivoted only through the rotation of the patient's head. Such rotation is limited or impeded in the aforementioned cases.
Another inconvenience is that during the introduction of the cannula, the anesthesiologist does not have means for seeing inside the larynx and generally along the entire path which the cannula travels.